Creating a formula for the Header to evaluate each record in Detail

I want to create a formula that notifies the user in the Header if there is a certain value in the report detail. I was able to create the formula but it only gave me the correct message when the 1st record in the detail had the value. Is there a way for it to read ALL records and if any of them have the value, to display the message?

Example:

Formula in Header: if ({@Total}>1) then "ERROR"

There are about 500 {@Total} fields in the detail and my formula only looks at the 1st one in the list.